THIS EXECUTIVE EMPLOYMENT AGREEMENT (this Agreement) is made and entered into as of the 31st
day of May 2008 (the Effective Date), by and between Ameristar Casinos, Inc., a Nevada
corporation, with its principal offices located at 3773 Howard Hughes Parkway, Suite 490S, Las
Vegas, Nevada 89169 (the Company), and Ray H. Neilsen (the Executive).

RECITALS

WHEREAS, the Company conducts a business in the gaming industry, including the operation of
casinos, hotels, restaurants and other similar amenities, and the Executive has substantial
expertise and experience in all aspects of the gaming industry; and

WHEREAS, the Executive has been employed on an at-will basis by the Company as Senior Vice
President since January 1, 2007, and has been employed by the Company or its subsidiaries in
various management positions since 1991; and

WHEREAS, the Company desires to continue to employ the Executive pursuant to the terms and
conditions of this Agreement, and the Executive has agreed to continue to be employed by the
Company on the terms and conditions set forth herein.

NOW, THEREFORE, in consideration of the promises and mutual covenants contained herein and for
other good and valuable consideration, the Company and the Executive (each individually a Party
and together the Parties) agree as follows:

TERMS AND CONDITIONS

1. DEFINITIONS. In addition to certain terms defined elsewhere in this Agreement, the
following terms shall have the following respective meanings:

1.1 Affiliate shall mean any Person that directly, or indirectly through one or more
intermediaries, controls or is controlled by or is under common control with the Person
specified. For purposes of this definition, control of a Person means the power, direct or
indirect, to direct or cause the direction of the management and policies of such Person
whether by contract or otherwise and, in any event and without limitation of the previous
sentence, any Person owning ten percent (10%) or more of the voting securities of another
Person shall be deemed to control that Person.

1.2 Base Salary shall mean the salary provided for in Section 3.1 of this
Agreement.

1.3 Board shall mean the Board of Directors of the Company.

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1.4 Cause shall mean that the Executive:

(a) has been formally charged with or convicted of a felony or any crime
involving fraud, theft, embezzlement, dishonesty or moral turpitude;

(b) has participated in fraud, embezzlement or other act of dishonesty
involving the Company;

(c) has been found unsuitable to hold a gaming license or has failed in a
timely manner to seek or obtain any finding of suitability or other approval by any
gaming regulatory authority whose license, finding of suitability or other approval
is legally required as a condition of the Executives performance of his duties and
responsibilities under this Agreement;

(d) has failed to fulfill or maintain all suitability and character
requirements for continued employment by the Company as from time to time may be
imposed pursuant to the Companys Gaming Compliance Program, written Company
policies or gaming laws, regulations or orders applicable to the Company or one of
its Affiliates;

(e) in carrying out his duties under this Agreement, has engaged in acts or
omissions constituting gross negligence or willful misconduct resulting in, or
which, in the good faith opinion of the Board could be expected to result in,
substantial economic harm to the Company;

(f) has failed for any reason, within ten (10) days of receipt by the Executive
of written notice thereof from the Company, to correct, cease or alter any action or
omission that (i) in the good faith opinion of the Board does or may materially and
adversely affect its business or operations, (ii) violates or does not conform with
the Companys policies, standards or regulations or (iii) constitutes a material
breach of this Agreement;

(g) has through willful or grossly negligent conduct disclosed any Confidential
Information without authorization except as otherwise permitted by this Agreement,
any other agreement between the Parties or any Company policy in effect at the time
of disclosure; or

(h) has failed for any reason, within ten (10) days of receipt by the Executive
of written notice thereof from the Company, to correct, cease or alter any action or
omission by which the Executive has breached his or her duty of loyalty to the
Company.

The Company shall have the burden of proving Cause in any dispute or proceeding
between the Company and the Executive.

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1.5 Change in Control Severance Plan shall mean the Ameristar Casinos, Inc. Change in
Control Severance Plan, as in effect on the date of this Agreement and as it may be amended
from time to time. The terms and conditions of such Plan shall be substantially similar
during the Executives employment under this Agreement as terms and conditions of comparable
deferred compensation arrangements for other senior executive officers of the Company in
effect from time to time.

1.6 Code shall mean the Internal Revenue Code of 1986, as amended, or any succeeding
provisions of law.

1.7 Company Property shall mean all items and materials provided by the Company to
the Executive, or to which the Executive has access, in the course of his employment,
including, without limitation, all Confidential Information and all other files, records,
documents, drawings, specifications, memoranda, notes, reports, studies, manuals, equipment,
keys, computer disks, videotapes, blueprints and other documents and similar items relating
to the Company, its Affiliates or their respective customers, whether prepared by the
Executive or others, and any and all copies, abstracts and summaries thereof.

1.8 Compensation Committee shall mean the Compensation Committee of the Board or
Persons performing similar functions.

1.9 Competing Business shall mean any Person engaged in the casino gaming industry
directly or through an Affiliate or subsidiary.

1.10 Confidential Information shall mean all Confidential Information as defined in
the Companys Confidentiality and Non-Disclosure Policy as in effect from time to time, the
current version of which has been executed by the Executive.

1.11 Deferred Compensation Plan shall mean the Companys Deferred Compensation Plan,
as in effect on the date of this Agreement and as it may be amended from time to time. The
terms and conditions of such Plan shall be substantially similar during the Executives
employment under this Agreement as terms and conditions of comparable deferred compensation
arrangements for other senior executive officers of the Company in effect from time to time.

1.12 Disability shall mean a physical or mental incapacity that prevents the
Executive from performing, with reasonable accommodation if necessary, the essential
functions of his position with the Company for a period of ninety (90) consecutive days as
determined: (a) in accordance with any long-term disability plan provided by the Company of
which the Executive is a participant; or (b) by a licensed healthcare professional selected
by the Company, in its sole discretion, to determine whether a Disability exists, to whom
the Executive hereby agrees to submit to medical examinations. In addition, the Executive
may submit to the Company documentation of a Disability, or lack thereof, from a licensed
healthcare professional of his choice.

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Following a determination of a Disability or lack of Disability by the Companys or the
Executives licensed healthcare professional, the other Party may submit subsequent
documentation relating to the existence of a Disability from a licensed healthcare
professional selected by such other Party. In the event that the medical opinions of such
licensed healthcare professionals conflict, such licensed healthcare professionals shall
appoint a third licensed healthcare professional to examine the Executive, and the opinion
of such third licensed healthcare professional shall be dispositive.

1.14 Good Reason as used in this Agreement shall mean and exist if, without the
Executives prior written consent, one or more of the following events occurs and the
Company fails for any reason, within fifteen (15) days of receipt by the Company of written
notice thereof from the Executive, to correct, cease or alter any action or omission causing
any such event(s):

(a) the Executive is assigned any significant duties or responsibilities that
are inconsistent with the scope of duties and responsibilities associated with the
Executives position as described in Section 2.3, including without
limitation the requirement that the Executive report to any person other than the
Board ;

(b) the Executive is required to relocate from, or maintain his principal
office outside of, a twenty-five (25) mile radius of his principal office location
as of the date of this Agreement;

(c) the Executives Base Salary is decreased by the Company;

(d) during the first twelve (12) months following a Change in Control (as
defined in the Change in Control Severance Plan), the failure of the Company to
award the Executive an annual bonus equal to at least seventy-five percent (75%) of
the average amount of the annualized bonus paid to the Executive for the last two
(2) full years;

(e) the Executive is excluded from participation in any employee benefit or
short-term incentive plan or program or his benefits under such plans or programs
are materially reduced in violation of Section 4.1 or any other provision of
this Agreement;

(f) the Company fails to pay the Executive any deferred payments that have
become payable under the Deferred Compensation Plan;

(g) the Company fails to reimburse the Executive for business expenses properly
incurred in accordance with the Companys policies, procedures or practices;

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(h) the Company fails to obtain a written agreement from any assignee of the
Company to assume the Companys obligations under this Agreement and the
Indemnification Agreement upon an assignment of this Agreement in a sale of assets
constituting a Change in Control;

(i) a material breach by the Company of its obligations under this Agreement,
the Indemnification Agreement or any written plan documents or agreements of the
Company defining equity award rights or employee benefit plan rights of the
Executive.

If the Company disputes the existence of Good Reason, the Company shall have the
burden of proving the absence of Good Reason.

1.15 Indemnification Agreement shall mean that certain Indemnification Agreement
currently in effect by and between the Company and the Executive.

1.17 Restricted Area shall mean the areas within a fifty (50) mile radius of any
location at which the Company or one of its Affiliates operates a casino, or has publicly
announced in good faith an intention to operate a casino, on the date of termination or
expiration of the Executives employment; provided, however, that (i) if the Company or one
of its Affiliates operates a casino, or has publicly announced in good faith an intention to
operate a casino, in the Las Vegas Strip and/or Las Vegas Downtown market areas but not in
the Las Vegas Locals market area, then the Restricted Area in respect of such casino or
casinos shall be applicable only to Las Vegas Strip and Las Vegas Downtown market area
casinos, and (ii) if the Company or one of its Affiliates operates a casino, or has publicly
announced in good faith an intention to operate a casino, in the Las Vegas Locals market
area but not in the Las Vegas Strip and/or Las Vegas Downtown market areas, then the
Restricted Area in respect of such casino or casinos shall be applicable only to Las Vegas
Locals market area casinos.

1.18 Restriction Period shall mean the period ending twelve (12) months after the
termination or expiration of the Term of Employment, regardless of the reason for such
termination or expiration.

1.19 Term of Employment shall mean the period specified in Section 2.2.

2. TERM OF EMPLOYMENT, POSITION AND RESPONSIBILITIES.

2.1 Employment Continued. The Company hereby continues the employment of the
Executive, and the Executive hereby accepts continued employment with the Company, for the
Term of Employment, in the position and with the duties and responsibilities set forth in
Section 2.3, and upon such other terms and subject to such other conditions as are
stated in this Agreement.

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2.2 Term of Employment. Unless earlier terminated pursuant to the provisions
of this Agreement, the initial Term of Employment shall terminate at the close of business
on May 30, 2009; provided, however, that the initial Term of Employment
shall thereafter automatically be extended for successive one-year terms, unless either
Party gives written notice of termination in accordance with Section 12 not less
than ninety (90) days prior to the expiration of the then current Term of Employment. In
the event that such notice is given, the Executives employment shall terminate at the close
of business on the last day of the then current Term of Employment and in that event that
date shall be the Executives last day of employment.

2.3 Title and Responsibilities.

(a) During the Term of Employment, the Executive shall be employed as Chairman
of the Board of Directors of the Company and will perform such other duties and
services as, from time to time, are reasonably required by the Board. The Executive
shall have such responsibilities as the Board may direct from time to time. The
Executive shall be elected by the Board as a corporate executive officer of the
Company at all times during the Term of Employment. The Executive will report
directly to the Board. During the Term of Employment, the Company will not reduce
the title or responsibilities of the Executive in any material respect.

(b) During the Term of Employment, the Executive shall devote substantially all
of his business time and attention to the business and affairs of the Company and
its subsidiaries and Affiliates and shall use his best efforts, skills and abilities
to promote the Companys interests. Notwithstanding the foregoing, the Executive
shall not be precluded from engaging in charitable and community affairs (including,
but not limited to the Executives continued service as co-trustee and a member of
the board of directors of The Craig H. Neilsen Foundation) and managing his personal
investments, as long as such activities do not materially detract from the
Executives performance of his duties under this Agreement. The Executive may serve
as a member of the board of directors (or the equivalent) of corporations and other
entities, subject to the approval of the Board.

3. COMPENSATION.

3.1 Base Salary. During the Term of Employment and effective as of the
Effective Date, the Executive shall be entitled to receive a base salary (the Base
Salary), payable in monthly or more frequent installments as shall be established by
the Company as its normal payroll practice from time to time or as required by applicable
law, at an annualized rate of no less than Five Hundred and Seventy-Five Thousand Dollars
($575,000), subject to reduction for any and all applicable federal, state and local
withholding, social security and unemployment taxes. Such Base Salary shall be reviewed
annually as of January 1, beginning January 1, 2009, for possible increase (but

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not decrease), in the discretion of the Compensation Committee. In conducting any such annual
review, the Compensation Committee shall consider any change in the Executives
responsibilities, the performance of the Executive, the financial performance of the Company
and other factors deemed pertinent by the Compensation Committee. Such increased Base
Salary shall then constitute the Executives Base Salary for purposes of this Agreement.

3.2 Annual Bonus.

(a) General. The Executive will be eligible to receive a discretionary
bonus for each fiscal year of the Company, beginning with the year ending December
31, 2008, at a target level of one hundred percent (100%) of the Executives
weighted average Base Salary for such fiscal year (Annual Bonus). The actual
Annual Bonus awarded will range from zero to two hundred percent (200%) of the
Executives weighted average Base Salary and will depend upon the Companys
financial performance (including, with respect to the Annual Bonus for the year
ending December 31, 2008, Company performance over the entire year), the Executives
merit performance and such other factors as the Compensation Committee may
determine.

(b) Supplemental 2008 Annual Bonus. In addition to the annual bonus
for the year ending December 31, 2008 to which the Executive is currently entitled
under the terms of the Companys Performance-Based Annual Bonus Plan, the Executive
shall be entitled to an additional discretionary bonus for the year ending December
31, 2008 in an amount such that, when combined with the annual bonus, if any, the
Executive earns under the terms of the Companys Performance-Based Annual Bonus Plan
as in existence prior to the Effective Date, the Executives total bonus payments
for such year equal the amount the Executive would have received under the Companys
Performance-Based Annual Bonus Plan for the year had the Executives target annual
bonus at the beginning of the year equaled 100% of his weighted average Base Salary
for the year.

3.3 Deferred Compensation. The Executive shall be eligible to participate in
the Companys Deferred Compensation Plan pursuant to the terms of that plan.

3.4 Equity Compensation. The Executive will be granted a number of
non-qualified stock options and restricted stock units during the Companys next annual
equity compensation award cycle. The number of shares subject to these awards will be
determined pursuant to the Companys equity compensation award program; provided,
however, that the Executives equity award allocation for such grant cycle shall be
based upon 200% of the Executives then-current Base Salary and shall reflect an A
performance grade. If approved by the Compensation Committee, these options and restricted
stock units will be made subject to the Companys standard terms and conditions for senior
executives and be evidenced by separate award agreements, the terms of which will
exclusively govern the awards. In addition to the above-described

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equity awards, commencing
in 2009, the Executive will be eligible to receive annual equity awards based on his
position, salary level, performance bonus grade and other factors in accordance with and
subject to the terms of the Companys equity compensation program as in effect from time to
time.

3.5 Change in Control Severance Plan. The Executive shall be eligible to
participate in the Change in Control Severance Plan as in effect from time to time.

4. EMPLOYEE BENEFIT PROGRAMS.

4.1 Pension and Welfare Benefit Plans. In addition to the benefits provided
for in Sections 3.3, 3.4 and 3.5, during the Term of Employment, the Executive shall
be entitled to participate in all employee benefit plans and programs made available to
similarly situated senior management personnel of the Company generally, as such programs
may be in effect from time to time, including, without limitation, pension and other
retirement plans, profit sharing plans, group life insurance, group health insurance, group
health supplemental insurance coverage through the Companys Exec-U-Care Medical Plan or a
substitute plan, accidental death and dismemberment insurance, long-term disability, sick
leave (including salary continuation arrangements), vacations, paid time off, holidays,
severance and change in control plans and programs and other employee benefit programs as
such plans and programs are exclusively described in written plan and program documents,
subject to the eligibility criteria, rules, plan provisions and regulations applicable to
such plans and programs and to the provisions of ERISA and the Code. The Executive shall be
eligible for primary and supplemental group health insurance beginning on his or her first
day of employment. Nothing contained herein shall be construed as negating or limiting the
ability of the Company to amend, modify or terminate any employee benefit programs or plans,
in its sole discretion. The Executives wage income subject to income taxation will include
certain imputed amounts in respect of the life insurance benefits and primary group health
plan benefits provided by the Company without cost to the Executive, but the Executive will
not be required to contribute to the cost of these programs except as set forth in the last
sentence of this Section. The amount of imputed income in respect of the primary group
health plan benefits will be measured by the premium contribution that otherwise would be
due from the Executive under the provisions of the plan but for the Companys waiver of the
Executives contribution requirements. The Executive will be responsible for making payment
through payroll deduction of premiums for group long-term disability coverage if the
Executive elects to enroll for such coverage; provided, however, that in such event, the
gross amount of each payroll installment received by the Executive will
be increased by an amount equal to any long-term disability premium deducted from such
installment.

4.2 Responsibility for Tax Liabilities. Except as may otherwise be expressly
provided in this Agreement, the Company shall not be responsible in any way for any income
or other tax liabilities of the Executive due in connection with the receipt by the
Executive of any compensation, benefits or perquisites from the Company.

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5. BUSINESS EXPENSE REIMBURSEMENT AND PERQUISITES.

5.1 Expense Reimbursement. During the Term of Employment, the Executive shall
be entitled to receive reimbursement by the Company for all reasonable out-of-pocket
expenses incurred by him in performing services under this Agreement, including any
relocation expenses in accordance with Company policies, subject to providing the proper
documentation of such expenses and to Company policies in effect from time to time with
respect thereto.

5.2 Perquisites. During the Term of Employment, the Executive shall also be
entitled, in accordance with Company policies in effect from time to time, to the following
perquisites:

(a) hotel, food and beverage complimentary privileges for business and personal
use at the properties operated by the Companys subsidiaries; and

(b) complimentary use of the Companys condominiums in Sun Valley, Idaho, for
so long as the Company leases such condominiums.

6. TERMINATION OF EMPLOYMENT.

6.1 Termination Due to Death or Disability. The Executives employment shall
be terminated immediately in the event of his or her death or Disability; provided, however,
that no termination on account of the Executives Disability will occur to the extent that
the Executives Disability is protected by the provisions of applicable federal, state or
local law. In the event of a termination due to the Executives death or Disability, the
Executive or his or her beneficiary designated pursuant to Section 14, or if none,
his or her estate, as the case may be, shall be entitled, in consideration of the
Executives obligations under Section 8 and in lieu of any other compensation
whatsoever, to:

(a) earned but unpaid Base Salary at the time of his or her death or
Disability;

(b) any Annual Bonus earned pursuant to Section 3.2, in respect of
employment during the entire calendar year preceding the calendar year in which
death or Disability occurs, but not yet paid;

(c) reimbursement for expenses incurred but not paid prior to such termination
of employment pursuant to Section 5.1;

(d) an amount equal to any accrued but unused vacation or other paid time off
as of the termination of employment;

(e) such rights to other benefits as may be provided in applicable written plan
documents and agreements of the Company, including, without

9

limitation, documents
and agreements defining equity award rights and applicable employee benefit plans
and programs, according to the terms and conditions of such documents and
agreements; and

(f) any and all amounts owed by the Company under Sections 6.1(a), 6.1(b),
6.1(c) and 6.1(d) shall be paid by the Company within fifteen (15) days of the
date of termination of employment. Any and all amounts owed by the Company under
Section 6.1(e) shall be paid at the later of sixty (60) days following the
date of termination or the date(s) specified under the applicable written plan
documents or agreements.

6.2 Termination by the Company for Cause. The Company may terminate the
Executives employment for Cause at any time during the Term of Employment by giving written
notice to the Executive that the Company intends to terminate his or her employment for
Cause. In the event of a termination for Cause, the Executive shall be entitled, in
consideration of the Executives obligations under Section 8 and in lieu of any
other compensation whatsoever, to:

(a) earned but unpaid Base Salary through the date of termination of
employment;

(b) any Annual Bonus earned pursuant to Section 3.2, in respect of
employment during the entire calendar year preceding the calendar year in which
termination occurs, but not yet paid;

(c) reimbursement for expenses incurred but not paid prior to such termination
of employment pursuant to Section 5.1;

(d) an amount equal to any accrued but unused vacation or other paid time off
as of the termination of employment;

(e) such rights to other benefits as may be provided in applicable written plan
documents and agreements of the Company, including, without limitation, documents
and agreements defining equity award rights and applicable employee benefit plans
and programs, according to the terms and conditions of such documents and
agreements; and

(f) any and all amounts owed by the Company under Sections 6.2(a), 6.2(b),
6.2(c) and 6.2(d) shall be paid by the Company within fifteen (15) days of the
date of termination of employment. Any and all amounts owed by the Company under
Section 6.2(e) shall be paid at the later of sixty (60) days following the
date of termination or the date(s) specified under the applicable written plan
documents or agreements.

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No termination for Cause and nothing in this Agreement shall waive or be deemed to waive any
rights or claims or remedies as may be available to the Company arising out of the facts
giving rise to such termination for Cause.

6.3 Termination by the Executive Without Good Reason. The Executive may
terminate his or her employment without Good Reason on his or her own initiative for any
reason or no reason upon thirty (30) days prior written notice to the Company. Such
termination shall have the same consequences as a termination by the Company for Cause under
Section 6.2.

6.4 Termination by the Executive for Good Reason. Notwithstanding any other
provision of this Agreement, the Executive may terminate his employment hereunder at any
time during the Term of Employment for Good Reason by giving thirty (30) days prior written
notice to the Company that the Executive intends to terminate his employment for Good Reason
and setting forth the basis of the Good Reason with reasonable specificity. In the event of
a termination by the Executive for Good Reason, the Executive shall be entitled, in
consideration of the Executives obligations under Section 8 and in lieu of any
other compensation and benefits whatsoever, to:

(a) an amount equal to two (2) times the Executives annual Base Salary at the
rate in effect at the time of his termination, which shall be paid out in equal
installments over twenty-four (24) months from the date of termination at the same
frequency as the Companys regular payroll payments;

(b) earned but unpaid Base Salary through the date of termination of
employment;

(c) any Annual Bonus earned pursuant to Section 3.2, in respect of
employment during the entire calendar year preceding the calendar year in which
termination occurs, but not yet paid;

(d) reimbursement for expenses incurred but not paid prior to such termination
of employment pursuant to Section 5.1;

(e) an amount equal to any accrued but unused vacation or other paid time off
as of the termination of employment;

(f) such rights to other benefits as may be provided in applicable written plan
documents and agreements of the Company, including, without limitation, documents
and agreements defining equity award rights and applicable employee benefit plans
and programs, according to the terms and conditions of such documents and
agreements;

(g) continuation of the Companys group health insurance (including Exec-U-Care
or substitute benefits) for the Executive and his eligible dependents,

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at the Companys expense, for eighteen (18) months after the termination of employment or,
at the Companys option, payment to the Executive of the economic equivalent
thereof, which shall constitute the provision of COBRA benefits to the Executive;
and

(h) any and all amounts owed by the Company under Sections 6.4(b), 6.4(c),
6.4(d) and 6.4(e) shall be paid by the Company within fifteen (15) days of the
date of termination of employment. Any and all amounts owed by the Company under
Sections 6.4(f) and 6.4(g) shall be paid at the later of sixty (60) days
following the date of termination or the date(s) specified in the applicable written
plan documents or agreements.

6.5 Termination by the Company Without Cause. Notwithstanding any other
provision of this Agreement, the Company may terminate the Executives employment without
Cause, other than due to death or Disability, at any time during the Term of Employment by
giving written notice to the Executive that the Company intends to terminate his employment
without Cause. In the event that the Company terminates the Executives employment without
Cause, the Executive shall be entitled, in consideration of the Executives obligations
under Section 8 and in lieu of any other compensation and benefits whatsoever, to:

(a) an amount equal to two (2) times the Executives annual Base Salary at the
rate in effect at the time of his termination, which shall be paid out in equal
installments over twenty-four (24) months from the date of termination at the same
frequency as the Companys regular payroll payments;

(b) earned but unpaid Base Salary through the date of termination of
employment;

(c) any Annual Bonus earned pursuant to Section 3.2, in respect of
employment during the entire calendar year preceding the calendar year in which
termination occurs, but not yet paid;

(d) reimbursement for expenses incurred but not paid prior to such termination
of employment pursuant to Section 5.1;

(e) an amount equal to any accrued but unused vacation or other paid time off
as of the termination of employment;

(f) such rights to other benefits as may be provided in applicable written plan
documents and agreements of the Company, including, without limitation, documents
and agreements defining equity award rights and applicable employee benefit plan
documents, according to the terms and conditions of such documents and agreements;

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(g) continuation of the Companys group health insurance (including
Exec-U-Care or substitute benefits) for the Executive and his eligible dependents,
at the Companys expense, for eighteen (18) months after the termination of
employment or, at the Companys option, payment to the Executive of the economic
equivalent thereof, which shall constitute the provision of COBRA benefits to the
Executive; and

(h) any and all amounts owed by the Company under Sections 6.5(b), 6.5(c),
6.5(d) and 6.5(e) shall be paid by the Company within fifteen (15) days of the
date of termination of employment. Any and all amounts owed by the Company under
Sections 6.5(f) and 6.5(g) shall be paid at the later of sixty (60) days
following the date of termination or the date(s) specified in the applicable written
plan documents or agreements.

6.6 Termination Due to Expiration of the Term of Employment. If either Party
elects not to extend the initial Term of Employment or any successive Term of Employment,
the Executive shall not be entitled to any additional compensation after the expiration
thereof except as may be expressly provided for herein, but such termination of employment
shall not otherwise affect accrued but unpaid compensation or benefits provided under this
Agreement or pursuant to any Company plan or program. Notwithstanding the foregoing, if the
Company elects not to extend the initial Term of Employment or any successive Term of
Employment, such election shall have the same consequences as a termination of the
Executives employment without Cause, effective as of the last day of the then current Term
of Employment, unless the Executives employment is otherwise terminated prior to the last
day of the then current Term of Employment, in which case the consequences of such
termination of employment shall be dependent upon the basis for such termination of
employment as provided in this Agreement.

7. CONDITIONS TO PAYMENTS UPON TERMINATION.

7.1 Timing of Payments. Unless otherwise provided herein, any payments to
which the Executive shall be entitled under Section 6 shall be payable upon the
satisfaction of the conditions set forth in this Agreement.

7.2 No Mitigation; No Offset. In the event of any termination of the
Executives employment under Section 6, the Executive shall be under no obligation
to seek other employment, and there shall not be offset against amounts due to the Executive
any remuneration attributable to any subsequent employment that the Executive may obtain.
Notwithstanding any contrary provision contained herein, in the event of any termination of
employment of the Executive, the exclusive remedies available to the Executive shall be the
amounts due under Section 6, which are in the nature of liquidated damages, and are
not in the nature of a penalty. The provisions of this Section 7.2 shall survive
the expiration or earlier termination of this Agreement.

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7.3 Compliance with the Agreement. No payments or benefits payable to the
Executive upon the termination of his employment pursuant to Section 6 shall be made
to the Executive if he fails to comply with all of the terms and conditions of this
Agreement, including, without limitation, Sections 8 and 9.

7.4 Payments upon Termination Conditioned on Release of Claims. Any payments
to the Executive under Section 6 shall be subject to the condition that the
Executive accepts and executes, without subsequent revocation, a release of claims
substantially in the form attached hereto as Exhibit A.

7.5 Continuing Obligations of the Executive. No act or omission by the
Executive in breach of this Agreement shall be deemed to permit the Executive to forego or
waive such payments in order to avoid his obligations under Section 8 or 9.

8. COVENANT NOT TO ENGAGE IN CERTAIN ACTS.

8.1 General. The Parties understand and agree that the purpose of the
restrictions contained in this Section 8 is to protect the goodwill and other
legitimate business interests of the Company, and that the Company would not have entered
into this Agreement in the absence of such restrictions. The Executive acknowledges and
agrees that the restrictions are reasonable and do not, and will not, unduly impair his
ability to make a living after the termination of his employment with the Company. The
provisions of this Section 8 shall survive the expiration or sooner termination of
this Agreement.

8.2 Non-Assistance; Non-Diversion. In consideration for this Agreement to
employ the Executive and the other valuable consideration provided hereunder, the Executive
agrees and covenants that during the Term of Employment and during the Restriction Period,
and except when acting on behalf of the Company or on behalf of any Affiliate of the
Company, the Executive shall not, directly or indirectly, for himself or any third party, or
alone or as a member of a partnership or limited liability company, or as an officer,
director, shareholder, member or otherwise, engage in the following acts:

(a) divert or attempt to divert any existing business of the Company or any
Affiliate of the Company;

(b) accept any position or affiliation or assignment with, or render any
services (whether as an independent contractor or employee) on behalf of, any
Competing Business within the Restricted Area;

(c) accept any position or affiliation or assignment or render any services
(whether as an independent contractor or employee) within the corporate, divisional
or regional headquarters or corporate, divisional or regional management group of
any Competing Business whose operations and properties include one or more casinos
within the Restricted Area; or

14

(d) hire or retain any employee of the Company or any Affiliate of the Company
to provide services for any other Person, or induce, solicit, attempt to solicit,
encourage, divert, cause or attempt to cause any employee or prospective employee of
the Company or any Affiliate of the Company to (i) terminate or leave such
employment or (ii) accept employment with anyone other than the Company or an
Affiliate of the Company.

8.3 Cessation/Reimbursement of Payments. If the Executive violates any
provision of this Section 8, the Company may, upon giving written notice to the
Executive, immediately cease all payments and benefits that it may be providing to the
Executive pursuant to Section 3, Section 4, and Section 6, and the
Executive shall be required to reimburse the Company for any payments received from, and the
cash value of any benefits provided by, the Company between the first day of the violation
and the date such notice is given; provided, however, that the foregoing shall be in
addition to such other remedies as may be available to the Company and shall not be deemed
to permit the Executive to forego or waive such payments in order to avoid his obligations
under this Section 8; and provided, further, that any release of claims by the
Executive pursuant to Section 7.4 shall continue in effect.

8.4 Survival. The Executive agrees that the provisions of this Section
8 shall survive the termination of this Agreement and the termination of the Executives
employment.

9. CONFIDENTIAL INFORMATION AND COMPANY PROPERTY.

9.1 Confidential Information. The Executive understands and acknowledges that
Confidential Information constitutes a valuable asset of the Company and its Affiliates and
may not be converted to the Executives own or any third partys use. Accordingly, the
Executive hereby agrees to comply with the terms of the Companys Confidentiality and
Non-Disclosure Policy as in effect from time to time, the current version of which has been
executed by the Executive.

9.2 Company Property. All Company Property is and shall remain exclusively the
property of the Company. Unless authorized in writing to the contrary, the Executive shall
promptly, and without charge, deliver to the Company on the termination of
employment hereunder, or at any other time the Company may so request, all Company
Property that the Executive may then possess or have under control.

9.3 Prohibition on Insider Trading; Communications with the Investment
Community. The Executive hereby agrees to comply with and be bound by the Companys
Insider Trading Policy and Guidelines for Public Disclosures and Communications with the
Investment Community, each as in effect from time to time, the current versions of which
have been executed by the Executive.

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9.4 Survival. The Executive agrees that the provisions of this Section
9 shall survive the termination of this Agreement and the termination of the Executives
employment.

10. MUTUAL ARBITRATION AGREEMENT.

10.1 Arbitrable Claims. All disputes between the Executive (and his attorneys,
successors, and assigns) and the Company (and its trustees, beneficiaries, officers,
directors, members, managers, Affiliates, employees, agents, successors, attorneys, and
assigns) relating in any manner whatsoever to the employment of or termination of employment
of the Executive, including, without limitation, all disputes arising under this Agreement
(Arbitrable Claims), shall be resolved by binding arbitration as set forth in this
Section 10, except for claims set forth in Section 10.4 (the Mutual
Arbitration Agreement). Arbitrable Claims shall include, but are not limited to: claims
brought under Title VII of the Civil Rights Acts of 1964, the Civil Rights Act of 1991, the
Age Discrimination in Employment Act of 1967 (including the Older Workers Benefit Protection
Act), the Americans with Disabilities Act, the Fair Labor Standards Act, the Equal Pay Act,
the Family and Medical Leave Act, ERISA, the Nevada Fair Employment Practices Act (NRS
613.010 et seq.), any state statutory wage claim under Chapter 608 of the Nevada Revised
Statutes, or any other applicable federal, state or local labor or fair employment law, all
as amended from time to time; claims for compensation; claims for breach of any contract or
covenant (express or implied); tort claims of all kinds; and all claims based on any
federal, state, or local law, statute or regulation. Arbitration shall be final and binding
upon the Parties and shall be the exclusive remedy for all Arbitrable Claims. THE PARTIES
HEREBY WAIVE ANY RIGHTS THEY MAY HAVE TO TRIAL BY JUDGE OR JURY IN REGARD TO ARBITRABLE
CLAIMS, EXCEPT AS PROVIDED BY SECTION 10.4.

10.2 Procedure. Arbitration of Arbitrable Claims shall be in accordance with
the National Rules for the Resolution of Employment Disputes of the American Arbitration
Association, as amended, and as augmented in this Agreement. Either Party may bring an
action in court to compel arbitration under this Agreement and to enforce an arbitration
award. Otherwise, neither Party shall initiate or prosecute any court action in any way
related to an Arbitrable Claim. All arbitration hearings under this Agreement shall be
conducted in Las Vegas, Nevada. Unless otherwise required by law or as may be required to
uphold the enforceability of this Mutual Arbitration Agreement, the fees and
costs of the arbitrator and of the American Arbitration Association shall be divided
equally between both Parties. Each Party will bear its own attorneys fees, and attorneys
fees will not be awarded to a prevailing Party.

10.3 Confidentiality. All proceedings and all documents prepared in connection
with any Arbitrable Claim shall be confidential and, unless otherwise required by law, the
subject matter and content thereof shall not be disclosed to any Person other than the
parties to the proceedings, their counsel, witnesses and experts, the arbitrator and, if
involved, the court and court staff.

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10.4 Applicability. This Section 10 shall apply to all disputes under
this Agreement other than disputes relating to the enforcement of the Companys rights under
Sections 8 and 9 of this Agreement and the Companys right to seek injunctive relief
as provided in Section 13.

10.5 Acknowledgment. The Executive acknowledges that he:

(a) has carefully read this Section 10;

(b) understands its terms and conditions; and

(c) has entered into this Mutual Arbitration Agreement voluntarily and not in
reliance on any promises or representations made by the Company other than those
contained in this Mutual Arbitration Agreement.

12. NOTICES. All notices, demands and requests required or permitted to be given to either
Party under this Agreement shall be in writing and shall be deemed to have been given when
delivered personally or sent by certified or registered mail, postage prepaid, return receipt
requested, duly addressed to the Party concerned at the address indicated below or to such changed
address as such Party may subsequently give notice of:

Ray H. Neilsen
at the current address on file with
the Company from time to time

13. RIGHT TO SEEK INJUNCTIVE RELIEF. The Executive acknowledges that a violation on his part
of any of the covenants contained in Sections 8 and 9 would cause immeasurable and
irreparable damage to the Company. The Executive accordingly agrees and hereby grants his consent
that, without limiting the remedies available to the Company, any actual or threatened violation of
such covenants may be enforced by injunctive relief or by other equitable remedies issued or
ordered by any court of competent jurisdiction.

14. BENEFICIARIES/REFERENCES. The Executive shall be entitled to select a beneficiary or
beneficiaries to receive any compensation or benefit payable hereunder following the Executives
death, and may change such election, by giving the Company written notice thereof. In the event of
the Executives death or a judicial determination of his incompetence,

17

reference in this Agreement
to the Executive shall be deemed, where appropriate, to refer to his beneficiary, estate or other
legal representative.

15. SURVIVORSHIP. The respective rights and obligations of the Parties hereunder shall
survive the expiration or any earlier termination of this Agreement to the extent necessary to the
intended preservation of such rights and obligations. The provisions of this Section 15
are in addition to the survivorship provisions of any other Section of this Agreement.

16. REPRESENTATIONS AND WARRANTIES. Each Party represents and warrants that he or it is fully
authorized and empowered to enter into this Agreement and that the performance of his or its
obligations under this Agreement will not violate any agreement between that Party and any other
Person.

17. ENTIRE AGREEMENT. This Agreement and the Indemnification Agreement and any
contemporaneous document expressly setting forth an agreement between the Parties and expressly
identified in this Agreement contain the entire agreement between the Parties concerning the
subject matter hereof and supersede all prior agreements, understandings, discussions, negotiations
and undertakings, whether written or oral, express or implied, between the Parties with respect
hereto. No representations, inducements, promises or agreements not embodied herein shall be of
any force or effect.

18. ASSIGNABILITY; BINDING NATURE. This Agreement shall be binding upon and inure to the
benefit of the Parties and their respective successors, heirs and assigns; provided, however, that
no rights or obligations of the Executive under this Agreement may be assigned or transferred by
the Executive, other than rights to compensation and benefits hereunder, which may be transferred
only by will or operation of law and subject to the limitations of this Agreement.

19. AMENDMENT OR WAIVER. No provision in this Agreement may be amended or waived unless such
amendment or waiver is agreed to in writing and signed by both Parties. No waiver by one Party of
any breach by the other Party of any condition or provision of this Agreement to be performed by
such other Party shall be deemed a waiver of a similar or dissimilar condition or provision at the
same or any prior or subsequent time. No failure of either Party to exercise any power given to
such Party hereunder or to insist upon strict compliance by
the other Party with any obligation hereunder, and no custom or practice at variance with the
terms hereof, shall constitute a waiver of the right of such Party to demand strict compliance with
the terms hereof.

20. SEVERABILITY. In the event that any provision or portion of this Agreement shall be
determined to be invalid or unenforceable for any reason, in whole or in part, the remaining
provisions of this Agreement shall be unaffected thereby and shall remain in full force and effect
to the fullest extent permitted by law. Without limiting the foregoing, if any portion of
Section 8 is held to be unenforceable, the maximum enforceable restriction of time, scope
of activities and geographic area will be substituted for any such restrictions held unenforceable.

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21. GOVERNING LAW. This Agreement shall be governed by and construed and interpreted in
accordance with the laws of the State of Nevada without reference to the principles of conflict of
laws thereof. In the event of any dispute or controversy arising out of or relating to this
Agreement that is brought to a court, the Parties mutually and irrevocably consent to, and waive
any objection to, the exclusive jurisdiction of any federal or state court of competent
jurisdiction sitting in Clark County, Nevada to resolve such dispute
or controversy; provided,
however, that nothing in this Section 21 shall affect the Parties agreement in Section
10 that arbitration under Section 10 shall apply to all disputes under this Agreement
other than as provided in Section 10.4.

22. INDEMNIFICATION. To the extent not otherwise required by law or the Indemnification
Agreement, the Company will consider in good faith, and consistent with the Companys past
practices, requests by the Executive for indemnification against claims arising from the
Executives conduct in the course and scope of the Executives employment under this Agreement and
for advancement of expenses reasonably incurred in defending against such claims.

23. SECTION 409A COMPLIANCE

23.1 A termination of employment shall not be deemed to have occurred for purposes of
any provision of this Agreement providing for the payment of any amounts or benefits upon or
following a termination of employment unless such termination is also a separation from
service within the meaning of Code Section 409A and the regulations and guidance
promulgated thereunder (collectively, Code Section 409A) and, for purposes of any such
provision of this Agreement, references to a termination, termination of employment or
like terms shall mean separation from service. If Executive is deemed on the date of
termination to be a specified employee within the meaning of that term under Code Section
409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is
specified as subject to this Section 23 or that is otherwise considered deferred
compensation under Code Section 409A payable on account of a separation from service, such
payment or benefit shall be made or provided at the date which is the earlier of (i) the
expiration of the six (6)-month period measured from the date of such separation from
service of the Executive or (ii) the date of Executives death (the Delay Period). Upon
the expiration of the Delay Period, all
payments and benefits delayed pursuant to this Section 23.1 (whether they would
have otherwise been payable in a single sum or in installments in the absence of such delay)
shall be paid or reimbursed to Executive in a lump sum without interest, and any remaining
payments and benefits due under this Agreement shall be paid or provided in accordance with
the normal payment dates specified for them herein.

23.2 With regard to any provision herein that provides for reimbursement of costs and
expenses or in-kind benefits, except as permitted by Code Section 409A, all such payments
shall be made on or before the last day of calendar year following the calendar year in
which the expense occurred.

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24. HEADINGS. The headings of the Sections and Subsections contained in this Agreement are
for convenience only and shall not be deemed to control or affect the meaning or construction of
any provision of this Agreement.

25. COUNTERPARTS. This Agreement may be executed in counterparts, each of which shall be
deemed an original and all of which shall constitute one and the same Agreement with the same
effect as if all Parties had signed the same signature page. Any signature page of this Agreement
may be detached from any counterpart of this Agreement and reattached to any other counterpart of
this Agreement identical in form hereto but having attached to it one or more additional signature
pages.

26. ACKNOWLEDGMENT. The Executive represents and acknowledges the following:

(a) he has carefully read this Agreement in its entirety;

(b) he understands the terms and conditions contained herein;

(c) he has had the opportunity to review this Agreement with legal counsel of
his own choosing, and either has done so or has intentionally elected not to do so,
and in any event he has not relied on any statements made by the Company or its
legal counsel as to the meaning of any term or condition contained herein or in
deciding whether to enter into this Agreement; and

(d) he is entering into this Agreement knowingly and voluntarily.

[signature page follows]

20

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the Effective Date.

THIS AGREEMENT CONTAINS A BINDING ARBITRATION PROVISION THAT MAY BE ENFORCED BY THE PARTIES.

AMERISTAR CASINOS, INC.

By:

/s/
Peter C. Walsh

Name:

Peter C. Walsh

Title:

Senior Vice President and General Counsel

EXECUTIVE:

/s/
Ray H. Neilsen

Ray H. Neilsen

21

Exhibit A

SEPARATION AGREEMENT
AND
GENERAL AND SPECIAL RELEASE

This Separation Agreement and General and Special Release (Agreement) is made by and between
Ray H. Neilsen (the Executive) and Ameristar Casinos, Inc., a Nevada
corporation (the Company), with respect to separation payments to be paid to the Executive
conditioned in part on a complete release by the Executive of any and all claims against the
Company and its affiliated entities, their respective directors, officers, employees, agents,
accountants, attorneys, representatives, successors and assigns.

In consideration of delivery to the Executive of the severance payments and benefits by the
Company conditionally promised by the Company in that certain Executive Employment Agreement by and
between the Executive and the Company dated as of May 31, 2008 (the Employment Agreement), and
with the sole exception of those obligations expressly recited herein or to be performed hereunder
and of the Executives claims to vested interests the Executive may have in employee benefit plans,
stock options or other equity awards as defined exclusively in written documents, the Executive and
the Executives heirs, successors and assigns do hereby and forever release and discharge the
Company and its affiliated entities and their past and present directors, officers, employees,
agents, accountants, attorneys, representatives, successors and assigns from any and all causes of
action, actions, judgments, liens, indebtedness, damages, losses, claims, liabilities and demands
of whatsoever kind and character in any manner whatsoever arising prior to the date of this
Agreement, including but not limited to any claim for breach of contract, breach of implied
covenant, breach of oral or written promise, allegedly unpaid compensation, wrongful termination,
infliction of emotional distress, defamation, interference with contract relations or prospective
economic advantage, negligence, misrepresentation or employment discrimination, and including
without limitation, to the extent permitted by law, alleged violations of Title VII of the Civil
Rights Act of 1964 prohibiting discrimination based on race, color, religion, sex or national
origin, the Civil Rights Act of 1991, the Age Discrimination in Employment Act of 1967 (including
the Older Workers Benefit Protection Act) prohibiting discrimination based on age over 40, the
Americans With Disabilities Act prohibiting discrimination based on disability, the Fair Labor
Standards Act, the Equal Pay Act, the Family and Medical Leave Act, the Employee Retirement Income
Security Act of 1974, the Nevada Fair Employment Practices Act (NRS 613.010 et seq.), any state
statutory wage claim under Chapter 608 of the Nevada Revised Statutes, and any other federal, state
or local labor or fair employment law under which a claim might be brought were it not released
here, all as amended from time to time.

The Executive assumes the risk of any mistake of fact and of any facts which are unknown, and
thereby waives any and all claims that this release does not extend to claims which the Executive
does not know or suspect to exist in his favor at the time of executing this release, which if
known by the Executive must or might have materially affected his settlement with the Company.

1

The Executive and the Company represent, understand and expressly agree that this Agreement
sets forth all of the agreements, covenants and understandings of the parties, superseding all
other prior and contemporaneous oral and written agreements with respect to the termination or
separation of the Executives employment excepting only those written agreements set forth or
referred to in the Employment Agreement, including without limitation the Companys Confidentiality
and Non-Disclosure Policy and the Companys Insider Trading Policy, which the Executive and the
Company reaffirm and incorporate herein by this reference and which shall survive indefinitely.
The Executive and the Company agree that no other agreements or covenants will be binding upon the
parties unless set forth in a writing signed by the parties or their authorized representatives,
and that each of the parties is authorized to make the representations and agreements herein set
forth by or on behalf of each such party. The Executive and the Company each affirms that no
promises have been made to or by either to the other except as set forth in the Employment
Agreement or this Agreement.

The Executive and the Company agree that any and all disputes, controversies or claims arising
out of this Agreement or concerning the Executives employment or its termination shall be
determined exclusively by final and binding arbitration pursuant to the terms of the Employment
Agreement, except as otherwise provided by the Employment Agreement.

2

The Executive acknowledges that he has had twenty-one (21) days within which to consider this
Agreement if he has wished to do so, that he has seven (7) days from the date of his acceptance of
this Agreement within which to revoke his acceptance, that he has been and hereby is advised by the
Company to consult with counsel concerning this Agreement and has had an opportunity to do so, and
that no payments will be made to the Executive by the Company hereunder until after such seven (7)
days and until the Executive shall have provided thereafter reasonable assurances on request that
he has not revoked his acceptance of this Agreement within such seven (7) days. The Executive
affirms that he enters into this Agreement freely and voluntarily.